ENVIRON MENTS

SIGNIFICANT PROGRESS HAS BEEN MADE TOWARD THE DEVELOPMENT OF A COMPREHENSIVE MECHANICAL PROPERTY DATA BASE FOR P100 GG/AL METAL MATRIX COMPOSITE MATERIAL. LITTLE OR NO DATA EXISTS RELATIVE TO THE ENVIROMENTAL BEHAVIOR OF THIS MATERIAL. THE PRESENT ANTICIPATED APPLICATION ENVIRONMENTS FOR THIS MATERIAL INCLUDE SEACOAST, SHIPBOARD, AND ENVIRONMENTS IN WHICH FOSSIL FUEL EXHAUSTS ARE PRESENT. THE PROPOSED PROGRAM WILL PROVIDE FOR THE CHARACTERIZATION OF GR/AL IN THESE ENVIRONMENTS. THE GR/AL WILL BE CHARACTERIZED WITH AND WITHOUT SURFACE PROTECTION. ADDITIONALLY, P100 GR/MG WILL BE CHARACTERIZED IN THESE ENVIRONMENTS. GR/MG IS RECEIVING SIGNIFICANT ATTENTION CURRENTLY BECAUSE OF THE ZERO COEFFICIENT OF THERMAL EXPANSION PROPERTY OF THIS MATERIAL. CORROSION BEHAVIOR OF THESE MATERIALS WILL BE COMPARED TO THE BEHAVIOR OF THE WROUGHT MATERIAL EXPOSED TO IDENTICAL TEST CONDITIONS. THE APPLICABILITY OF ELECTROCHEMICAL LINEAR POLARIZATION RESISTANCE TECHNIQUES TO THE ENVIRONMENTAL CHARACTERIZATION OF THESE MATERIALS WILL BE DEMONSTRATED. THIS TECHNIQUE PROVIDES A MORE EXPEDIENT METHOD FOR EVALUATION OF GENERAL CORROSION THAN THE TRADITIONAL COUPON EXPOSURE TESTS. THE PROPOSED PROGRAM WILL PROVIDE THE FOUNDATION FOR A COMPREHENSIVE PHASE II ENVIRONMENTAL CHARACTERIZATION OF THE METAL MATRIX COMPOSITES.